The Roman Catholic Relief Act, passed by Parliament in 1829, was the culmination of the process of Catholic Emancipation throughout Britain. In Ireland it repealed the Test Act and the remaining Penal Laws which had been in force since the passing of the Disenfranchising Act of the Irish Parliament of 1728. During the campaign for Catholic emancipation in Ireland, Daniel O'Connell, organizer of the Catholic Association, was the main leader of the campaign but many others were active as well, both for and against. As the Roman Catholic Relief Act was being passed by parliament, there was a rise of unionism, which divided protestant unionists and catholic republicans in 1829, and this effectively meant many different factors impacted more negatively than positively on the Anglo-Irish relation.
Catholic emancipation gave many Catholics a new sense of political power, and was directed into the Tithe War of 1831. Tithes, which was a tax of 10% paid on crops and animals by all denominations for the upkeep of the Anglican Church of Ireland, had caused much resentment towards parliament from Irish Catholics, as it was irrespective of an individual's religious adherence. The secondary source written by Brian Jenkins, Era of Emancipation, published 1988: British Government of Ireland, explains that ‘’the government blithely ignored all warnings, private as well as public, that the taxes were extremely unpopular, and were uniting Ireland against Britain, for it was infected with a new spirit.’’ This shows how the taxes angered the Irish Catholics, as they were getting harshly taxed, for nothing in return, such as Catholics being able to stand for parliament and take their seat. In the beginning of the 1830’s the resistance became more organised and many refused to pay. Therefore, as Irish Catholics begun to refuse the Tithes, the Anglo-Irish relation weakened, England and Ireland partitioned more.